Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0012833 (dizziness)
 9,689 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The chemistry, pharmacology, pharmacokinetics, assay methodologies, adverse effects, and dosage of levamisole are described, and the clinical studies of levamisole therapy in patients with colorectal carcinoma are reviewed. Levamisole is a synthetic, orally active agent that has antihelmintic and immunomodulatory properties. It is capable of inducing T-cell differentiation and restoring depressed effector functions of peripheral lymphocytes and phagocytes to normal. The drug is well absorbed from the gastrointestinal tract after oral administration and is extensively metabolized by the liver. Gas chromatography and high-performance liquid chromatography are the most common methods used to measure concentrations of levamisole in biologic fluids. Levamisole combined with fluorouracil has been associated with a one-third reduction in recurrence and risk of death in patients with surgically resected Dukes stage C colon cancer; this combination is now recommended as standard therapy in these patients. Uses in patients with rectal carcinoma, Dukes stage B colon cancer, metastatic colon cancer, other malignancies, or nonmalignant disorders remain investigational. Common adverse effects include nausea, abdominal pain, vomiting, diarrhea, metallic or altered taste, flulike symptoms, mood elevation, insomnia, hyperalertness, dizziness, and headache. The most serious adverse effect associated with levamisole is granulocytopenia. The FDA-approved dosage of levamisole is 50 mg orally every eight hours for three days every two weeks. Levamisole therapy is to be initiated no earlier than 7 and no later than 30 days after surgery and is to be continued for one year. Levamisole combined with fluorouracil has been associated with a one-third reduction in recurrence and risk of death in patients with resected stage C colon cancer. Further research is needed to more clearly define the mechanism of action, optimum dose and scheduling, and clinical efficacy of levamisole in treating other malignancies.
 ...
PMID:Levamisole in the adjuvant treatment of colon cancer. 200 37

Clinical signs and lesions of levamisole toxicosis include: nausea, vomiting, increased salivation, frequent urination and defecation, colic, dizziness, headache, muscle tremors, ataxia, anxiety, hyperesthesia with irritability, clonic convulsions, depression, rapid respiration, dyspnea, prostration, collapse, hemorrhages in the subepicardium and thalamus, enteritis, hepatic degeneration and necrosis, and splenic congestion. Most of these signs and lesions are similar to those observed in nicotine poisoning. Levamisole causes vasopressor and panting effects which are blocked by ganglionic blocking agents hexamethonium and mecamylamine but are not blocked by atropine. The vasopressor effect of levamisole is blocked by alpha-adrenergic antagonists phentolamine and dibenamine; however, the respiratory effect of levamisole is not affected by these alpha-adrenergic antagonists. Repeated IV injections of levamisole cause a tachyphylactic response. With levamisole-induced tachyphylaxis, the effects of other ganglionic stimulants dimethylpiperazinium and nicotine are also abolished. Levamisole causes an electroencephalographic arousal which is antagonized by atropine sulfate and mecamylamine. There is also a structural similarity of levamisole to nicotine. These studies suggest that levamisole is a nicotine-like compound. Possible treatment of levamisole poisoning is discussed. Drug interactions of levamisole with organophosphates and anthelmintics, eg, pyrantel, methyridine, and diethylcarbamazine, are also discussed.
 ...
PMID:Toxicity and drug interactions of levamisole. 721 95

Two female patients with an adenocarcinoma of the colon (Duke stages B and C) underwent colectomy followed by adjuvant chemotherapy combining 5 fluorouracil (5 FU) and levamisole. Secondary neurological manifestations occurred in both patients including vertigo, nausea and vomiting, dizziness with loss of balance, slow ideation, impaired memory, headache and, on one case, central origin facial paralysis. Symptoms appeared between the 11th and 34th week of treatment. The patients had received 9 to 30 g 5 FU and 2.7 to 7.6 g levamisole. CT scan and/or MRI first suggested cerebral metastases then demyelinisation. The clinical signs disappeared spontaneously in less than one month. The brain images were unchanged. The 5 FU/levamisole combination was undoubtedly responsible for the neurological manifestations. Levamisole may have potentialized the effect of 5 FU leading to demyelinisation. Whether chemotherapy should be stopped or not is debated.
 ...
PMID:[Multifocal inflammatory leukoencephalopathy: a complication of chemotherapy by fluorouracil and levamisole]. 774 17